Reinforced inflatable packer



April 1, 1958 w. D. MQUNcE REINFORCED INFLATABLE PACKER 3 Sheets-Sheet 1Filed July 7, 1955 A TTOR/VEY.

prl l, 1958 w. D. MoUNcE REINFORCED INFLATABLE PACKER s sheets-sheet 2Filed July 7, 1955 2 L ,..Ctb

INVENTOR.

Whitman D. MOL/nce /V/J/ @y 1f-M 21x12 3 Sheets-Sheet 3 Filed July 7,1955 F/AG. Z

INVENTOR. WIr/'Iman D. Mou/we,

#Ma TM A T TORNE Y.

United States Patent O REINFORCED INFLATABLE PACKER Whitman D. Mounce,Houston, Tex., assigner, by mesue assignments, to Esso Research andEngineering Company, Elizabeth, N. J., a corporation of DelawareApplication July 7, 1955, Serial No. 520,424

Claims. (Cl. 16o-187) This invention relates to well packers. Moreparticuularly, this invention relates to an improved well packer ofsturdy construction which will not leas or brealsunder the highpressures often found in well operations.

This invention is a continuation-in-part of my copending applicationSerial No. 417,559 filed March 22, 1954, in the name of Whitman D.Mounce, now Patent No.A 2,779,419.

In well operations, a packer is often used to seal off a portion of thewell in order to carry out certain operations above or below thelocation of the packer. instances, two packers are used verticallyspaced from each other in order to seal off specific formations for tliepurpose of taking drill stem tests. It is essential while carrying outthe aforementioned operations that one have a packer which can bedepended on under very high pressures. A great many packers have beendevised which usually include a Yrubber resilient member which isinflated in order to seal off the area to be investigated. These rubberpackers have often been not sturdy enough to withstand the highpressures which may reach 50G In some pounds per square inch or more,and have tended to leak i.

Vor break. In attempts to provide a packer which can withstand the highpressures often found within a well, packers have been constructed whichinclude a resilient expansible tubular member mounted about a shaft ortubing. The resilient expansible tubular member is connected, at itsextremities, to an upper plate and a lower plate, at least one of saidplates being slidable. Reinforcement cables, such as steel cables, maybe included in the resilient expansible tubular member. However, if theplatel at the high pressure end is free to move on the shaft and theload of the hydrostatic head is carried by the plate at the low pressureend, there is a tendency for the reinforced rubber packer to be forcedinto the annular space between the low pressure end plate and theborehole wall. This produces sharp kinks in the reinforcing cables whichprevent the packer from returning to its original diameter whendeflated. On the other hand, if the end plate at the high pressure endof the packer is fixed and the low pressure end is free to slide, nocable kinking occurs, but the full load of the fluid column is carriedby the reinforcing cables, which limits the load which can be carried tothe tensile strength of these cables. The reason the full load iscarried by the cables is that if the plate on the low pressure end isfree to slide without restraint,

it offers no support to the load and the entire load is carexpansibletubular member a very sturdy packer can be constructed which willwithstand a very high pressure. The combination of my new reinforcingmeans included f. ICC

in the expansible tubular member and a hydraulic load adjusting systemproduces a well packer which is very sturdy and capable of withstandingpressures far greater than the pressures which former well packers havebeen able to withstand.

Briefly described, my new inflatable well packer has a means formaintaining tension on the resilient inflatable packer therebypreventing the formation of kinks in the packer. The tensioning meansmay, for example, include a hollow cylindrical top support, which isfilled with liquid before the packer is inflated and slidably mountedabout a shaft. The cylindrical topV supportY has dise posed therein acylindrical. member which isrelatively stationary and rests on thebottom of the cylinder when the packer is not inflated. The cylindricalmember extends laterally from said shaft. At least one liquid passagewayis provided within the shaft and leads from the hollow cylinder so as topermit the flow of liquid from the cylinder upon any downward movementof said hollow cylinder, the downward movement causing the cylindricalmember to force the liquid through the liquidpassageway. The liquidpassageway leads to a space defined by a second cylindrical member alsomounted upon the shaft and having an upturned flanged portion and alower packer plate. The second cylindrical member serves to confine theliquid flowing into it and also serves to guide said lower packer plate.By thismeans, after the well packer has been inflated, any pressureexerted against the packer, such as the pressure of a fluid column, istransmitted through the liquid passageway to the upper cylindricalsupport thereby tensioning the inflatable resilient packer andv dividingtheload of the fluid column between the top support member and bottomsupport member. The reinforcing means of my newimprovedV packer mayinclude a pleated sock which is arranged about reinforcing cables to aidin the reinforcement of thetubular expansible member. The cylindricalsock which is pleated about its periphery, preferably is located alongthe lower por-v tion of the tubular expansible member as it is alongthis portion that knking Vand breaking of the tubular expansible memberoccurs."V An alternative reinforcing means disclosed consists of abraided tubular member which is disposed between aninner expansibletubularrmember and an outer eXpansible' tubular member.

Various other objects, advantages and features of my invention willbecome more apparent from the following description taken in conjunctionwith the accompanying drawing, in which Fig. 1 is a sectionalelevational View of one embodiment of my improved packer shown in thedeflated position;

of Fig. 1 shown in an inflated position;

Fig. 3 is an elevational View showing the manner in which thereinforcing sock is arranged to reinforce the cables of the embodimentof Fig. 1; l

Fig. 4 is a View taken along line 4 4 of Fig. 3 showing the position ofthe sock when the packer is in the deflated position;

Fig. 5 is a view similar to Fig. 4 showing the position of the sock whenthe tubular expansible member is in the inflated position;

Fig. 6 is a sectional elevational view of another modification of my newimproved well packer;

Fig. 7 is an elevational view partly in section showing the braidedtubular member utilized in the embodiment shown in Fig. 6; and

Fig. 8 is an elevational view partly in section showing the braidedtubular member utilized in the embodiment shown in Fig. 6 when thepacker has been inflated.

Referring to the drawing, and specifically to Fig. 1,

Fig. 2 is a sectional elevational view of the embodiment numeral 3indicates a well into which my new packer has been inserted. Though onepacker is shown in the drawing, it is to be understood that if it isdesired to carry on operations which necessitate the use of two or morepackers, my invention can be equally effective by utilizing any numberof packers each of which is of a similar construction to that shown inFig. l. The packer is supported by a cylindrical shaft 4 about which aredisposed an upper cylindrical plate member `5 and a lower cylin dricalplate member 6. Plate members 5 and d are coaxial lwith the shaft 4 andare vertically spaced from each other. Connected to said plate members 5and 6 by vulcanization and bonding is a resilient and expansible tubularmember 7. Plates 5 and 6 are movable longitudinally along shaft 4 and'hence move toward Vone another when Vthe resilient member 7 isinflated. in order to provide a sturdier resilient member 7, a pluralityof reinforcement cableslS may be imbedded longitudinally in saidresilient and expansible member '7. Cables 8 may desirably be made ofsteel although it will be understood that other suitable material may beemployed. To further reinforce my new packer at the lower portion of thetubular member 7, where failure would most likely occur, a spring sock30 is also imbedded within the rubber expansible tubular member 7. As analternative, the sock 3G may be made of nylon cord.

In order to iniiatethe packer 7, a tubular passageway 10 is provided.This passageway is connected to a pump (not shown) or any other suitablemeans for inflating and deflating the packer member 7 and opens into theannular space between resilient member 7 and shaft 4. A lower end platecylindrical receiving member 11 having an annular flanged portion 12 isintegrally connected to the cylindrical shaft 4, the cylindricalreceiving member 11 serving to slidably receive the lower end platemember 6. The lower end plate member 6 has a reduced diameter portion13. The reduced diameter portion 13 fits snugly into the annular flangedportion 12 of the receiving member 11.

A cylindrical cap 14 is integrally connected to the top support plate 5thereby formingwith said top support plate 5 a hollow cylindrical member156. Integrally connected to the cylindrical shaft member 4 is a solidcylindrical member 15 which is disposed within the hollow cylinder. Thiscylindrical member 15 is stationary and downward movement of the hollowcylinder 16, when the inllatablepacker 7 is inflated, results in thesolid cylindricalv member 15V forcing liquid contained within the hollowcylinder 16 through a liquid passageway`17 located in shaft 4 and into achamber 18 (Fig. 2) defined by plated and receiving member 11.

When the packer is utilized for taking drill stem tests,

l an additional passageway 9 (shown in'dotted lines) must be put intoshaft 4, passageway 9 serving to conduct to the surface the formationfluid to be tested.

in Fig. 2 there is shown my new improved packer in an inflated position.As is shown in Fig. 2,- the upper plate 5 and the lower plate 6 havemoved toward each other thereby forcing the liquid contained within thehollow cylindrical member 16 through the passageway 17 into the space 18which is formed between the lower plate member 6 and the receivingmember 11 due to the upper movement of the lower plate member 6. Theliquid contained in space 19, the liquid passageway 17 and the space 18,remains the'same in volume because any decrease in volume in space 19results in an equal increase in volume in space 1S since the crosssectional areas of the spaces 19 and 18 are the same. Hence there is nolongitudinal movement of the resilient tubular member 7 during itslateral expansion.

To prevent the escape of liquid through the small spaces between theslidingsurfaces of Vmy new packer, it is advisablerto include rubberO-ring 20 in a'groove formed in cap 14, rubber O-ring 21, placed in agroove'formed in the cylindrical member 15, rubber O-ring 22, in a thepacker leaves the wall of the hole.

groove formed in place member 5 and rubber O-rings 23 and 24 in groovesformed in plate member 6.

Figs. 3, 4 and 5 illustrate the arrangement of the lower portion of thecables 8 and the soclr member 30. The sock member 3d is of asubstantially cylindrical shape having its periphery folded to formoutwardly facing pleats 31 and inwardly facing pleats 32. Both theoutwardly facing pleats 31 and the inwardly facing pleats 32 are formedby fitting steel or other strong reinforcing material about the cables 8so as to provide vertically stacked pleats.

The sock member 3Q may be formed by winding annealed spring wire about aseries of pins of the proper size and position, and then heat treatingthem in place to obtain the desired tensile strength and elasticity ofthe spring material. The sock member is then taken olf the forming pinsand snapped into position on the vertical supporting cables at the lowpressure end of the packers. Rubber is then moulded onto the packer.Each of the cables 8 is disposed within an outwardly facing pocket 33formed by a vertical stack of inwardly facing pleats.

Fig. 4 and Fig. 5 are views showing the positions of the cables andpleats when the expansible tubular member 7 is deflated and inflated,respectively. As shown in Fig. '4, when the packer is in the deflatedposition the base of the pockets formed by the pleats 31 and 32 arerelatively nar'- row and the height is relatively long when compared tothe base and height of the pockets formed by the pleats 31 and 32 whenthe expansiible tubular member 7 is in the inflated position. Thisexpansion of the base of the pockets is caused by the tension on thepleats 31 andv 32 as a result of the pressure applied against theinflatable member 7 by the inllation iluid.

As previously stated, when a packer is inflated 'under high pressuresthere is a strong tendency of the'deformable rubber tubular member toextrude through the reinforcing means. This extrusion most often occursat the lower end of the tubular member below the point where Forthis'reason, the spring sock 30 is placed just above the lower 'platemember 6, as shown in Figs. l and 2. A reinforcing means, inorder toprevent the extrusion of the rubber material when high pressures areapplied, must lbe ableto stretch to half again its Yoriginal length Vandreturn `toits original length when the packer is dellated.`,"Former'reinforcing means, such as barrel hoops, do not satisfy theforegoing requirements. My new spring sock 30,"however, satisfies theserequirements. The springsock 30, when expanded under high pressures,flexibly retains the expanding rubber tubular member 7. Also, thepressure exerted against the pockets formed by the outwardly facingpleats is transmitted to the cables 8. Furthermore, the spring sock 30does not restrain the vertical supporting cables from assuming thecurvature they tend to as'- sume where the inflated packer leaves thewall of the hole.

Fig. 6 shows a further modification of my new improved inatable packerutilizing an inner expansible tubular member 40 and an outer expansibletubular member 41 separatedby a braided reinforcing means 42 in place ofthe single expansible tubular member 7 and the cables 8 reinforced bythe spring sock 30, as shown in the modification of Figs. l and 2.Located at each end of the expansible tubular member 40 is a sleeve 43.Sleeve 43 is arranged coaxially with shaft 4 and 'is of a cylindricalshape having a continually decreasing outside diameter. Provided withineach of the sleeves 43 is a cup 44 having a rounded bottom 4S and llaredsides 46. The outer expansible tubular member 41'is bonded to a wedgemember 47. The wedge member 47 serves to wedge the longitudinal ends ofbraided means 42 against the sleeve member 43. To provide an additionalgripping action against the ends of the braided member 42 the taperingsurface '43 of sleeve member 43 is knurled.

To effect the. wedging action of wedge 47 and the knurled surface 43' ofsleeve '43 extensions 48 are provided inthe upper plate and the lowerplate 6. YThe upper cylindrical member i6 and the lower plate member -6are screwed upon the base of sleeve members 43 into tight engagementagainst the ibase 49 of the wedge members 47. The pressure of extensions48 against the bases 49 of wedge members-47 presses the longitudinalexten* sions of braided mem-ber 42 against the knurled surfaces ofsleeve 43 to hold the braided member in tight engagement. The ends ofthe inflatable sleeve 4t) form lip portions 40' which are fittinglyarranged in the cups 44 of the members 43. As seen more clearly in Fig.6, the lip portions 40 extend along the shaft 4 to provide chambers 44which fluidly communicate with passageway 1f? upon the application offluid pressure to the inflatable member 40. The pressure is applied tothe interior of the packer and enterslthe fluid chambers 44 to seal theinterior of the lip portions 40 of the inflatable member 4l) against theshaft 4` thereby preventing escape of fluid pressure.

,'Figs. 7 and 8 are views showing the positions of the braided tubularmember 42 in the deflated position and inflated position, respectively.in Figs. 7 and 8 the outer tubular expansible member di has beenpartially removed to more'clearly show the action and configuration ofthe braided member 42. The braided member consists of interwoven metalbands 50. Each of the interwoven metal bands 50 is made from elongatedstrings of metal which are arranged closely adjacent one another to formthe :metal bands 50. The bands 50 are each arranged helically between.theupper support member. and the lower support member.

In operation, therefore, the packer is first lowered into the well tothe location where it is desired to either seal ofi` the well againstthe well bottom, or in the case where two packers are utilized, to sealoff the formation 'between the two packers, to take tests of specificformations within the well. The packer is then inflated by means of tube10 until it fits firmly against the side of the well. After the packerhas been inflated, any pressure such as that due to the hydrostatic mudcolumn exerted on the packer tends to push plate member 6 downwardly.This pressure is transmitted through the liquid in space 1S, tube 17 andspace 19 to the upper portion of the hollow cylindrical member 16. Theupper portion of member 16 is integrally connected to the upper plate 5so that the force exerted against the upper portion of the cylindricalmember is also exerted on the upper plate 5. Hence the expansible packermembers are maintained under tension and no kinks will form within themembers. Also, the hydrostatic load is divided between end plates 5 and6 in order that a greater load may be carried than would be possibleotherwise. Further reinforcement of the tubular expansible members thuspermitting an even higher pressure to be exerted upon the tubular packermember is provided by reinforcing means such as the spring sock Sti orthe braided tubular member 42.

The above described packer -apparatus is given only for illustrativepurposes and should not be regarded as limiting the invention the scopeof which is set forth in the following claims.

I claim:

1. A well packer comprising a shaft, first and second spaced apartsupporting means slidably arranged on said shaft, spaced apart memberseach having outer inwardly tapering knurled surfaces and inner cupshaped surfaces connected to each of said supporting means,respectively, a reinforcing sleeve engaging with said knurled surfacesadjacent the ends thereof, first and second wedge members engaging withsaid first and second supporting means respectively `and having inwardlytapering surfaces parallel to said first and second knurled surfacesrespectively engaging with said reinforcing sleeve adjacent the endsthereof, an outer expansible sleeve member secured to said wedge membersadjacent each end thereof, an inner inflatable sleeve member surroundingsaid shaft and forming sealing means including vcups adjacent the endsthereof, a fluid passageway in said shaft communi` cating with theinterior of said inflatable member adapted to supply fluid to inflatesaid inflatable member and to fluidly communicate with said fluidchambers to` seal said inflatable member to said shaft adjacent the endsthereof.

2. A device as recited in claim l including a first stationary memberarranged on said shaft cooperating with said first supportingmeans toprovide a first fluid chamber above said stationary member, a secondstationary member arranged on said shaft cooperating with said secondsupporting means to provide a second fluid chamber below said secondsupporting means and means in said shaft fluidly intercommunicatingsaidfirst and second chambers.

3. A device as recited in claim 1 wherein said reinforcing sleevecomprises helically arranged braided bands.

4. A well packer comprising a shaft, rst and second spaced apartsupporting means slidably'arranged on said shaft, reinforcing meanssurrounding said shaft, wedging means arranged on said shaft adapted tosecure the ends of said reinforcing means, an inflatable sleeve membersurrounding said shaft and formed to provide means including cupsadjacent the ends thereof adapted to seal off fluid how between saidsleeve and said shaft, a first stationary member arranged on said shaftco-operating with said first supporting meansn to provide alrst fluidchamber above said first stationary member, a second stationary memberarranged on said shaft co-operating with said second supporting means toprovide a second fluid chamber below said second supporting means, meansin said shaft uidly intercommunicating said first and second chambersand a fluid passageway in said shaft communicatingv with the interior ofsaid inflatable member adapted to supply fluid to inflate saidinflatable member and seal the ends of said inflatable member to saidshaft.

5. A device as recited in claim 4 wherein said reinforcigig meanstherefor comprises helically arranged braided ands.

6. A device as recited in claim 4 wherein said reinforcing meanscomprises a cylindrical sock arranged adjacent one end of saidinflatable sleeve member and cables extending the length of saidinflatable sleeve member, the sock being cylindrically configured andformed to provide inwardly and outwardly facing pleats, said cablesbeing arranged in said inwardly facing pleats.

7. A well packer comprising a shaft, first and second spaced apartsupporting means slidably arranged onsaid shaft, reinforcing meanssurrounding said shaft, means arranged on said shaft adapted to securethe ends of said reinforcing means, an inflatable sleeve membersurrounding said shaft and formed to provide means including cupsadjacent the ends thereof adapted to seal oil. fluid flow between saidsleeve and said shaft, a rst stationary member arranged on said shaftcooperating with said first supporting means to provide a first fluidchamber above said first stationary member, a second stationary memberarranged on said shaft cooperating withv said second supporting means toprovide a second fluid chamber below said second supporting means,means' in said i shaft fluidly intercommunicating lsaid first and secondchambers and a fluid passageway in said shaft communieating with theinterior of said inflatable member adapted to supply fluid to inflatesaid inflatable member and seal the ends of said inflatable member tosaid shaft.

8. A well packer comprising a shaft, first and second spaced apartsupporting means slidably arranged on said shaft, reinforcing meanssurrounding said shaft, means arranged on said s haft adapted to securethe ends of said reinforcing means, an inflatable sleeve membersurrounding said shaft, the ends of which are formed to provide lipportions engaging with saidshaft, said lip portions forming uidchambers, a fluid passageway in said shaft communicating with theinterior of said inflatable member and said fluid chambers adapted tosupply fluid to inflate said inflatable member and seal the ends of saidasaasas inflatable member to said shaft, said reinforcing meanscomprising a single layered cylindrical helically configured ybraidedsheath, a first stationary member arranged on said shaft cooperatingwith said rst supporting means to provide a first fluid chamber abovesaid first stationary member, al second stationary member arranged onsaid shaft cooperating with said second supporting means to provide asecond fluid chamber below said second supporting means, and means insaid shaft fluidly intercommunicating said rst and second chambers.

9. A well packer comprising a shaft, first and second spaced apartsupporting means slidably arranged on said shaft, reinforcing meanssurrounding said shaft, means arranged on said shaft adapted to securethe ends of said reinforcing means, an inflatable sleeve membersurrounding said shaft, the ends of which `are formed -to provide lipportions engaging with said shaft, said lip portions ,forming fluidchambers, a fluid passageway in said shaft communicating with theinteriorfof said inflatable member and with said fluid chambers adaptedto supply fluid to inflate said inatable member and ,seall the ends ofsaid inatablemember tosaid shaft, said reinforcing means comprising asingle layered cylindrical helicallyI braided sheath extendingsubstantially the length of said sleeve member. j

l0. A well packer comprising a shaft, rst and second lsupporting meansslidably arranged on said shaft, spaced apart members each having outerinwardly tapering knurled surfaces and inner cup-shaped surfacesscrewthreadedly connected to said supporting means, reinforcing meanssurrounding said shaft and engaging with said ltnurled` surfacesadjacent the ends thereof, said reinforcing means including acylindrical pleated sock arranged adjacent one end of said inflatablesleeve member and cables extending the length of said inflatable sleevemember, first and second wedge members engaging with said first Iandsecond supporting means, respectively, and having inner inwardlytapering surfaces parallel to said rst and second knurled surfaces,respectively, engaging with said reinforcing means adjacent the endsthereof, an outer eX-pansible sleeve member secured to said wedgemembers adjacent the inner ends thereof, an inner inatable sleeve memberarranged adjacent said shaft and having sealing lip portions at the endsthereof, said lip portions being fittingly arranged on said cup-shapedsurfaces and the surfaces of said shaft adjacent thereto to provide cupsin said inflatable sleeve, a fluid passageway in said shaftcommunicating with the interior of said inatable member adapted tosupply fluid to inflate said inflatable member and seal said inflatablemember to said shaft adjacent the ends thereof.

References Cited in the le'of this patent UNITED STATES PATENTS FewelAug. 16, 1.955

